Brian Dunbar
Headquarters, Washington, D.C.
October 29, 1993
(Phone: 202/358-1547)
Myron Webb
Stennis Space Center, Miss.
(Phone: 601/688-3341)
RELEASE: 93-198
NASA-RUSSIAN MISSION EXPLORES KAMCHATKAN VOLCANOES
Preliminary results from an historic U.S.-Russian scientific
expedition are shedding new light on the geology of Eastern
Russia.
The data was obtained in August and September by NASA and
Russian scientists using NASA's Learjet Model 23 based at the John
C. Stennis Space Center, Miss.
The expedition, on which a Russian served as co-pilot and
translator, studied a variety of sites on the Kamchatkan peninsula
to provide remote-sensing imagery and field data. These data will
be used to study the geologic evolution of the volcanoes, the
impact of large volcanic eruptions on the atmosphere and its
chemistry.
The data also will be used to model thermal and dynamical
aspects of volcanoes. Carrying NASA's Thermal Infrared
Multispectral Scanner (TIMS) and a Zeiss camera, the plane flew
the first civilian research mission over Russian territory.
"The Kamchatka area is geologically significant because three
of the plates of the Earth's crust are converging in that area,"
said Dr. Miriam Baltuck, Chief of the Solid Earth Branch of NASA's
Office of Mission to Planet Earth. "The Pacific plate, which
contains most of the Pacific Ocean, is sliding beneath the
Eurasian and North American plates. When one plate descends, or
subducts beneath another, it heats up and partially melts. The
molten material generated from this process rises to the surface
through the overriding plates and erupts through volcanoes."
In the Western Pacific, this process has formed the arcs of
islands that rim the Pacific and also is responsible for deadly
earthquakes. The Kliuchevskoi volcano, one of the larger
volcanoes on the peninsula, has been mildly active since April
with small summit eruptions and emissions of sulfur dioxide and
ash plumes.
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Kamchatkan volcanoes also are capable of more energetic
eruptions, similar to the 1991 eruption of Mount Pinatubo in the
Philippines. Such eruptions can inject ash, sulfur dioxide and
aerosols_small solid or liquid particles that become suspended in
the atmosphere_high into the atmosphere where they can affect
global temperatures and ozone levels.
The program resulted from 4 years of negotiations between
NASA and the Russian Academy of Sciences, under the auspices of
the Volcanology Implementation Team of the U.S.-Russian Earth
Science Joint Working Group. With the support of numerous U.S.
and Russian agencies a new, direct air corridor was approved
between Shemya Air Force Base, Alaska, and Elisovo, Russia. This
new air corridor, which avoided an exhaustive northern ferry
route, should appear on future aeronautical charts.
As part of the agreement, Oleg Gusev, a Russian citizen,
served as co-pilot and translator aboard the Learjet. He is the
first Russian to serve as a crew member on a NASA aircraft and
only the second Russian to co-pilot a U.S. government aircraft --
the first was in 1943 during World War II.
"This is the first time, to our knowledge, that a U.S.
civilian research aircraft has flown over the territory of the
former Soviet Union," said Dr. Jim Hunning, Manager of the
Airborne Science Office in NASA's Office of Mission to Planet
Earth. "It has opened up a new avenue of research and air
transportation for science and commerce."
The expedition data have clarified the structure of the
volcanic areas and found evidence of the processes that created
them. An image of Tolbachik Volcano, for example, showed
solidified lava flows from eruptions in 1975 and 1976. The
younger flow proved richer in silicon and aluminum, with the older
flow richer in magnesium and calcium. The texture of the flows
appears to belie the chemical analyses which shows that the older
flow has the steep margins and ridges associated with a more
viscous lava while the younger flow appears to have been more
fluid.
Another site, Bezymianny Volcano, showed many similarities to
Mount St. Helens in Washington state. Bezymianny's eruption on
March 30, 1956, like Mount St. Helens' in 1980, was directed
largely to the side instead of upward. The Bezymianny eruption
reduced the elevation of the volcano by approximately 660 feet
(201 meters). The explosion is believed to have raised an ash
column to altitude of more than 22 miles (35 kilometers).
Inside the Bezymianny crater, a lava dome has grown to a
height of 1,650 feet (500 meters). A similar dome exists on Mount
St. Helens, and the temperature data on Bezymianny will be
compared to that from the Mount St. Helens dome, which has been
the subject of TIMS surveys over the past 4 years. The comparison
data can be used to develop models describing the thermal and
physical evolution of volcanoes.
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The floor of the Uzon Caldera, which was formed approximately
100,000 years ago, is the site of vigorous geothermal activity,
including geysers and hot springs. A temperature map developed
from the TIMS data will allow scientists to estimate the
geothermal input to the groundwater system.
Spectral data from the Gorely Volcano will allow scientists
to study the structure of more than 8,000 years of volcanic flows.
With this historical record, geologists can better understand how
the continuing subduction of the Earth's crust manifests itself on
the surface through volcanoes.
Overall, the data will help scientists understand volcanic
eruptions, frequency and magnitude and the effects of those
eruptions on the atmosphere. The science team also will evaluate
the data for development of a Volcano Global Impact Index which
would link geological and weather data and evaluate their combined
global impact.
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Note to Editors: Photos and infrared images illustrating this
story are available to news media representatives by contacting
NASA's Broadcast and Imaging Branch on 202/358-1900.
Tolbachik Volcano: Color: 93-HC-427 B&W: 93-H-475
Bezymianny Volcano: Color: 93-HC-428 B&W: 93-H-476